//本人没写过。。只是书上有。。。就写给你看看。。使用appletviewer运行该程序 //我还没运行你运行看看。。。 import java.awt.*; import java.awt.event.*; import java.applet.Applet;
public class CalulatorApplet extends Applet implements ActionListener { private TextField display; private double arg = 0; private String op = "="; private boolean start = true; public void init () { setLayout (new BorderLayout() ); display = new TextField("0"); display.setEditable(true); add(display,"north"); Panel p = new Panel(); p.setLayout(new GridLayout (4,4)); String buttons = "123+456-789*0.=/"; for (int i = 0; i <buttons.length(); i++ ){ Button b = new Button(buttons.substring(i,i+1)); p.add(b); b.addActionListener(this);//在按钮上注册动作监听器 } add(p,"Center"); }//end init() public void actionPerfored(ActionEvent ev){ Stirng s = ev.getActionCommand(); if('0' <= s.charAt(0) && s.charAt(0) <= '9' || s.equals(".")){ if(start) display.setText(s); else display.setText(display.getText()+s); start = false; } else { if(start){ if(s.equals("-")){ display.setText(s); start = false; } else { op = s; } } else { calculate (Double.parseDouble(display.getText())); op = s; start = true; } } }//end actionPerformed() public void calculate(double n){ if(op.equals("+")) arg += n; else if(op.equals("-")) arg -= n; else if(op.equals("*")) arg *= n; else if(op.equals("/")) arg /= n; else if(op.equals("=")) arg = n; display.setText(double.toString(arg)); } }//end CaculatorApplet class
这个只是个框架还没加功能呢!!!! 你也可以看看!!!! import javax.swing.*; import java.awt.*; public class Computer extends JApplet { JPanel p1=new JPanel(); JPanel p2=new JPanel(); JPanel p3=new JPanel(); JPanel p4=new JPanel(); JPanel p5=new JPanel(); JPanel p6=new JPanel(); public void init() { BorderLayout b1=new BorderLayout(); getContentPane().add(p1); p1.setLayout(b1); p1.add(p2,BorderLayout.NORTH); p1.add(p3,BorderLayout.CENTER); JTextField kk=new JTextField(30); p2.add(kk); BorderLayout b2=new BorderLayout(); p3.setLayout(b2); p3.add(p4,BorderLayout.NORTH); p3.add(p5,BorderLayout.WEST); p3.add(p6,BorderLayout.CENTER);
FlowLayout f=new FlowLayout(FlowLayout.LEFT); p4.setLayout(f); JButton a1=new JButton(" "); JButton a2=new JButton("Backspace"); JButton a3=new JButton(" CE "); JButton a4=new JButton(" C "); p4.add(a1); p4.add(a2); p4.add(a3); p4.add(a4);
GridLayout g1=new GridLayout(4,1); p5.setLayout(g1); JButton c1=new JButton("MC"); JButton c2=new JButton("MR"); JButton c3=new JButton("MS"); JButton c4=new JButton("M+"); p5.add(c1); p5.add(c2); p5.add(c3); p5.add(c4);
GridLayout g2=new GridLayout(4,5); p6.setLayout(g2); JButton w1=new JButton("7"); JButton w2=new JButton("8"); JButton w3=new JButton("9"); JButton w4=new JButton("/"); JButton w5=new JButton("sqrt"); JButton w6=new JButton("4"); JButton w7=new JButton("5"); JButton w8=new JButton("6"); JButton w9=new JButton("*"); JButton w0=new JButton("%"); JButton q1=new JButton("1"); JButton q2=new JButton("2"); JButton q3=new JButton("3"); JButton q4=new JButton("-"); JButton q5=new JButton("1/x"); JButton q6=new JButton("0"); JButton q7=new JButton("+/-"); JButton q8=new JButton("."); JButton q9=new JButton("+"); JButton q0=new JButton("="); p6.add(w1); p6.add(w2); p6.add(w3); p6.add(w4); p6.add(w5); p6.add(w6); p6.add(w7); p6.add(w8); p6.add(w9); p6.add(w0); p6.add(q1); p6.add(q2); p6.add(q3); p6.add(q4); p6.add(q5); p6.add(q6); p6.add(q7); p6.add(q8); p6.add(q9); p6.add(q0); } }